title: Role of long-chain acyl-coenzyme A synthetases in the regulation of arachidonic acid metabolism in interleukin 1β-stimulated rat fibroblasts.
abstract: Acyl coenzyme A synthetase long-chain family members (ACSLs) are a family of enzymes that convert long-chain free fatty acids into their acyl-CoAs and play an important role in fatty acid metabolism. Here we show the role of ACSL isozymes in interleukin (IL)-1β-induced arachidonic acid (AA) metabolism in rat fibroblastic 3Y1 cells. Treatment of 3Y1 cells with triacsin C, an ACSL inhibitor, markedly enhanced the IL-1β-induced prostaglandin (PG) biosynthesis. Small interfering RNA-mediated knockdown of endogenous Acsl4 expression increased significantly the release of AA metabolites, including PGE2, PGD2, and PGF2α, compared with replicated control cells, whereas knockdown of Acsl1 expression reduced the IL-1β-induced release of AA metabolites. Experiments with double knockdown of Acsl4 and intracellular phospholipase A2 (PLA2) isozymes revealed that cytosolic PLA2α, but not calcium-independent PLA2s, is involved in the Acsl4 knockdown-enhanced PG biosynthesis. Electrospray ionization mass spectrometry of cellular phospholipids bearing AA showed that the levels of some, if not all, phosphatidylcholine (PC) and phosphatidylinositol species in Acsl4 knockdown cells were decreased after IL-1β stimulation, while those in control cells were not so obviously decreased. In Acsl1 knockdown cells, the levels of some AA-bearing PC species were reduced even in the unstimulated condition. Collectively, these results suggest that Acsl isozymes play distinct roles in the control of AA remodeling in rat fibroblasts: Acsl4 acts as the first step of enzyme for AA remodeling following IL-1β stimulation, and Acsl1 is involved in the maintenance of some AA-containing PC species.
authors.affiliation: Division of Health Chemistry, Department of Healthcare and Regulatory Sciences, School of Pharmacy, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan. Electronic address: kuwata@pharm.showa-u.ac.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kuwata
authors.forename: Makiko
authors.initials: M
authors.lastname: Yoshimura
authors.forename: Yuka
authors.initials: Y
authors.lastname: Sasaki
authors.forename: Emiko
authors.initials: E
authors.lastname: Yoda
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Nakatani
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kudo
authors.forename: Shuntaro
authors.initials: S
authors.lastname: Hara
mesh_terms: D000818:Animals; D002460:Cell Line; D003066:Coenzyme A Ligases / Q000235:genetics / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D006801:Humans; D053583:Interleukin-1beta / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D010713:Phosphatidylcholines / Q000235:genetics / Q000378:metabolism; D054467:Phospholipases A2 / Q000235:genetics / Q000378:metabolism; D011453:Prostaglandins / Q000096:biosynthesis* / Q000235:genetics; D051381:Rats
chemical_list: D053583:Interleukin-1beta; D010713:Phosphatidylcholines; D011453:Prostaglandins; D054467:Phospholipases A2; D003066:Coenzyme A Ligases; C561832:Acsl1 protein, rat
keywords: AA; AACOCF(3); ACSL; Arachidonic acid; COX; Ca(2+)-independent PLA(2); Cyclooxygenase; ESI; Glycerophospholipid; HETE; HHT; IL; LC; MRM; MS; PC; PE; PG; PI; PLA(2); Phospholipase A(2); Prostaglandins; acyl-CoA synthetase long-chain family member; arachidonic acid; arachidonyl trifluoromethyl ketone; cPGES; cPLA(2); cyclooxygenase; cytosolic PGE synthase; cytosolic PLA(2); electrospray ionization; hydroxyeicosatetraenoic acid; hydroxyheptadecatrienoic acid; iPLA(2); interleukin; liquid chromatography; mass spectrometry; multiple reaction monitoring; phosphatidylcholine; phosphatidylethanolamine; phosphatidylinositol; phospholipase A(2); prostaglandin; sPLA(2); secreted PLA(2)